key papersKey paper

A phase 2a clinical study on the safety and efficacy of individualized dosed mebendazole in patients with advanced gastrointestinal cancer

A Swedish trial gave mebendazole to ten people with advanced bowel and stomach cancers that had stopped responding to treatment; it was safe, but every patient's cancer kept growing, four of them unusually fast.

Patients with treatment-refractory gastrointestinal cancer received mebendazole at individually adjusted doses up to 4 g a day aiming at a serum level of 300 ng/mL; 11 were included and 10 started treatment (Mebendazole phase 2a 2021). Two stopped before and the remaining eight after the eight-week CT scan, all for progressive disease, four met suggested criteria for hyperprogression, only five reached the target level, and no severe adverse effects were observed; the authors conclude that new approaches such as prodrugs or combinations would be needed for further exploration (Mebendazole phase 2a 2021).

Translational studyHas not changed practice yet11 participants

Authors

Mansoori S, Fryknäs M, Alvfors C, Loskog A, Larsson R, Nygren P.

Published

Scientific Reports, 2021

Full text

doi:10.1038/s41598-021-88433-y PubMed 33903692

Findings

10 treated; all 10 stopped for progressive disease by the eight-week scan; four met hyperprogression criteria.
No severe adverse effects; only five reached the target serum concentration.

What it means

The only completed efficacy study of an internet-famous dewormer in cancer patients found no benefit in anyone. It is the clearest human result in this whole story.

Caveats